Gathering research data

ABSTRACT

Methods and systems are provided for gathering research data. Frequency domain data is received or produced, a signature is extracted from the frequency domain data and an ancillary code is read from the frequency domain data.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation-in-part of nonprovisional patentapplication Ser. No. 10/256,834, filed Sep. 27, 2002 and assigned to theassignee of the present invention, and which is hereby incorporatedherein by reference in its entirety.

BACKGROUND

Methods and systems for gathering research data are disclosed.

There is considerable interest in identifying and/or measuring thereceipt of, and or exposure to, audio data by an audience for use byadvertisers, media outlets and others.

The emergence of multiple, overlapping media distribution pathways, aswell as the wide variety of available user systems (e.g. PC's, PDA's,portable CD players, Internet, cellular telephones, appliances, TV,radio, etc.) for receiving audio data, has greatly complicated the taskof measuring audience receipt of, and exposure to, individual programsegments. The development of commercially viable techniques for encodingaudio data with program identification data provides a crucial tool formeasuring audio data receipt and exposure across multiple mediadistribution pathways and user systems.

One such technique involves adding an ancillary code to the audio datathat uniquely identifies the program signal. Most notable among thesetechniques is the PPM methodology developed by Arbitron Inc., which isalready providing useful audience estimates to numerous mediadistributors and advertisers.

An alternative technique for identifying program signals is extractionand subsequent matching of “signatures” of the program signals. Suchtechniques typically involve the use of a reference signature database,which contains a reference signature for each program signal the receiptof which, and exposure to which, is to be measured. Before the programsignal is broadcast, these reference signatures are created by measuringthe values of certain features of the program signal and creating afeature set or “signature” from these values, commonly termed “signatureextraction”, which is then stored in the database. Later, when theprogram signal is broadcast, signature extraction is again performed,and the signature obtained is compared to the reference signatures inthe database until a match is found and the program signal is therebyidentified.

Past designs of audience measurements systems, like that shown in U.S.Pat. No. 5,481,294 to Thomas et al., have comprised separate meteringapparatuses comprising their own distinct code reading and signatureextraction capability. Information obtained by each apparatus is thencommunicated to a central site for processing to produce audiencemeasurement reports. These reports, based on the information obtained,provide data reflecting program exposure.

In obtaining information used in the generation of its reports, theabove system is substantially reliant on low levels of background noiseand hardwired connections to televisions and radios.

Such constraints make use of the above system(s) impractical whenunfettered portability of the metering apparatuses is desirable. Suchportability thereof may be desirable in any given number of situationswhen, for example, connection to a device reproducing media, such as atelevision or radio, is not feasible, especially where it is desired tomonitor out-of-home media exposure.

In a system like that shown in Thomas et al., the process of audiencemeasurement is overly complicated by virtue of the use of multiplemetering apparatuses. Because of such use, an excessive amount of poweris consumed, so that the system is inefficient. It is particularlyill-suited for use in a portable metering device that must rely on aninternal power source, such as a battery.

In systems where audience measurement is an additional function of adevice (such as a PDA or cellular telephone), it would be particularlyadvantageous to provide such functionality in the most efficient manner.To this end, it would be advantageous to minimize usage for this purposeof the processing power and working memory of the device to avoidslowing or otherwise interfering with additional capabilities offered bydevices not dedicated to the task of audience measurement. Additionally,whether a portable metering device is or is not dedicated to the task ofaudience measurement, the power supply thereof, typically a battery, canbe exhausted prematurely where excessive power is required to implementthis function. Thus, it would be advantageous to provide theabove-mentioned media monitoring capabilities while minimizingoccurrence of the disadvantages discussed.

It would be advantageous to provide methods and systems for thegathering of data concerning the usage of media data that enable anaudience member to undertake such activity no matter the situation orlocation in which media data is available.

It would also be advantageous to provide such methods and systems whichgather such data that are useful for determining exposure both toencoded and unencoded media, whether in-home or out-of-home, and whichprovide the ability to employ portable monitors that are small andunobtrusive and have low power requirements.

It would further be advantageous to provide such methods and systemswhich gather such data by decoding ancillary codes and extractingsignatures in an efficient manner reducing power and processingrequirements.

DISCLOSURE

For this application, the following terms and definitions shall apply:

The term “data” as used herein means any indicia, signals, marks,symbols, domains, symbol sets, representations, and any other physicalform or forms representing information, whether permanent or temporary,whether visible, audible, acoustic, electric, magnetic, electromagneticor otherwise manifested. The term “data” as used to representpredetermined information in one physical form shall be deemed toencompass any and all representations of corresponding information in adifferent physical form or forms.

The terms “media data” and “media” as used herein mean data which iswidely accessible, whether over-the-air, or via cable, satellite,network, internetwork (including the Internet), print, displayed,distributed on storage media, or by any other means or technique that ishumanly perceptible, without regard to the form or content of such data,and including but not limited to audio, video, audio/video, text,images, animations, databases, broadcasts, displays (including but notlimited to video displays, posters and billboards), signs, signals, webpages, print media and streaming media data.

The term “research data” as used herein means data comprising (1) dataconcerning usage of media data, (2) data concerning exposure to mediadata, and/or (3) market research data.

The term “presentation data” as used herein means media data or contentother than media data to be presented to a user.

The term “ancillary code” as used herein means data encoded in, addedto, combined with or embedded in media data to provide informationidentifying, describing and/or characterizing the media data, and/orother information useful as research data.

The terms “reading” and “read” as used herein mean a process orprocesses that serve to recover research data that has been added to,encoded in, combined with or embedded in, media data.

The term “database” as used herein means an organized body of relateddata, regardless of the manner in which the data or the organized bodythereof is represented. For example, the organized body of related datamay be in the form of one or more of a table, a map, a grid, a packet, adatagram, a frame, a file, an e-mail, a message, a document, a report, alist or in any other form.

The term “network” as used herein includes both networks andinternetworks of all kinds, including the Internet, and is not limitedto any particular network or inter-network.

The terms “first”, “second”, “primary” and “secondary” are used todistinguish one element, set, data, object, step, process, function,activity or thing from another, and are not used to designate relativeposition, or arrangement in time or relative importance, unlessotherwise stated explicitly.

The terms “coupled”, “coupled to”, and “coupled with” as used hereineach mean a relationship between or among two or more devices,apparatus, files, circuits, elements, functions, operations, processes,programs, media, components, networks, systems, subsystems, and/ormeans, constituting any one or more of (a) a connection, whether director through one or more other devices, apparatus, files, circuits,elements, functions, operations, processes, programs, media, components,networks, systems, subsystems, or means, (b) a communicationsrelationship, whether direct or through one or more other devices,apparatus, files, circuits, elements, functions, operations, processes,programs, media, components, networks, systems, subsystems, or means,and/or (c) a functional relationship in which the operation of any oneor more devices, apparatus, files, circuits, elements, functions,operations, processes, programs, media, components, networks, systems,subsystems, or means depends, in whole or in part, on the operation ofany one or more others thereof.

The terms “communicate,” and “communicating” and as used herein includeboth conveying data from a source to a destination, and delivering datato a communications medium, system, channel, network, device, wire,cable, fiber, circuit and/or link to be conveyed to a destination andthe term “communication” as used herein means data so conveyed ordelivered. The term “communications” as used herein includes one or moreof a communications medium, system, channel, network, device, wire,cable, fiber, circuit and link.

The term “processor” as used herein means processing devices, apparatus,programs, circuits, components, systems and subsystems, whetherimplemented in hardware, software or both, and whether or notprogrammable. The term “processor” as used herein includes, but is notlimited to one or more computers, hardwired circuits, signal modifyingdevices and systems, devices and machines for controlling systems,central processing units, programmable devices and systems, fieldprogrammable gate arrays, application specific integrated circuits,systems on a chip, systems comprised of discrete elements and/orcircuits, state machines, virtual machines, data processors, processingfacilities and combinations of any of the foregoing.

The terms “storage” and “data storage” as used herein mean one or moredata storage devices, apparatus, programs, circuits, components,systems, subsystems, locations and storage media serving to retain data,whether on a temporary or permanent basis, and to provide such retaineddata.

The terms “panelist,” “panel member,” “respondent” and “participant” areinterchangeably used herein to refer to a person who is, knowingly orunknowingly, participating in a study to gather information, whether byelectronic, survey or other means, about that person's activity.

The term “household” as used herein is to be broadly construed toinclude family members, a family living at the same residence, a groupof persons related or unrelated to one another living at the sameresidence, and a group of persons (of which the total number ofunrelated persons does not exceed a predetermined number) living withina common facility, such as a fraternity house, an apartment or othersimilar structure or arrangement, as well as such common residence orfacility.

The term “activity” as used herein includes, but is not limited to,purchasing conduct, shopping habits, viewing habits, computer usage,Internet usage, exposure to media, personal attitudes, awareness,opinions and beliefs, as well as other forms of activity discussedherein.

The term “research device” as used herein shall mean (1) a portable userappliance configured or otherwise enabled to gather, store and/orcommunicate research data, or to cooperate with other devices to gather,store and/or communicate research data, and/or (2) a research datagathering, storing and/or communicating device.

The term “portable user appliance” (also referred to herein, forconvenience, by the abbreviation “PUA”) as used herein means anelectrical or non-electrical device capable of being carried by or onthe person of a user or capable of being disposed on or in, or held by,a physical object (e.g., attaché, purse) capable of being carried by oron the user, and having at least one function of primary benefit to suchuser, including without limitation, a cellular telephone, a personaldigital assistant (“PDA”), a Blackberry device, a radio, a television, agame system (e.g., a Gameboy® device), a notebook computer, a laptopcomputer, a GPS device, a personal audio device (such as an MP3 playeror an iPod® device), a DVD player, a two-way radio, a personalcommunications device, a telematics device, a remote control device, awireless headset, a wristwatch, a portable data storage device (e.g.,Thumb™ drive), a camera, a recorder, a keyless entry device, a ring, acomb, a pen, a pencil, a notebook, a wallet, a tool, a flashlight, animplement, a pair of glasses, an article of clothing, a belt, a beltbuckle, a fob, an article of jewelry, an ornamental article, a shoe orother foot garment (e.g., sandals), a jacket, and a hat, as well as anydevices combining any of the foregoing or their functions.

Portable meters are disclosed that implement an ability to readancillary codes in audio media as well as an ability to extractsignatures from audio media to gather information concerning media towhich an audience member has been exposed. The meter carries out atransformation of received audio media data from a time domain to afrequency domain and makes use of the transformed audio media data bothto read an ancillary code therein and to extract a signature therefrom.Since a common transformation is used both for reading a code and forextracting a signature therefrom, the processing and working memoryresources of the portable device required for implementing the functionsof the audience meter are advantageously reduced. Likewise, the audiencemetering functionality thus imposes lower energy demands on the dataprocessing and storage resources of the portable meter.

A method of gathering research data in a portable monitoring device isprovided. The method comprises receiving time domain audio media data ina portable monitoring device of an audience member; converting the timedomain audio media data to frequency domain data; and processing thefrequency domain data for reading an ancillary code therefrom and forextracting a signature therefrom.

A portable audience monitoring system is provided. The system comprisesan input arranged to receive time domain audio media data; and aprocessor coupled with the input to receive the time domain audio mediadata therefrom and configured to convert the time domain audio mediadata to frequency domain data, and to process the frequency domain datato read an ancillary code therefrom and to extract a signaturetherefrom.

A method of gathering research data is provided. The method comprisesreceiving frequency domain data comprising data representing values ofmedia data in different respective frequency bands; and reading anancillary code from the frequency domain data and extracting a signaturefrom the frequency domain data.

A further method of gathering research data is provided. The methodcomprises receiving media data in portable audience monitoring device;converting the media data to a frequency domain to produce frequencydomain data; and extracting a signature from the frequency domain dataand reading an ancillary code therefrom.

FIG. 1 is a functional block diagram for use in illustrating methods andsystems for gathering research data.

FIG. 2 is a flow diagram for use in illustrating methods for gatheringresearch data.

FIG. 3 is a functional block diagram of a system for gathering researchdata.

FIG. 4 is a diagram of a further system for gathering research data.

FIG. 4A is a functional block diagram for use in explaining certainembodiments of the system of FIG. 4.

FIG. 5 is a diagram of a further system for gathering research data.

FIG. 6 is a diagram illustrating a method of identifying research datagathered by one or more of the systems disclosed herein.

FIG. 7 is a diagram of a further system for gathering research data.

FIG. 7A is an exploded view of a PUA with a research data monitoraffixed thereto.

FIG. 7B is a block diagram of the PUA according to FIG. 7A coupled witha research data monitor.

FIG. 7C is a block diagram of the research data monitor of FIGS. 7A and7B.

FIG. 7D is a layout diagram of an embodiment of the research datamonitor of FIGS. 7A, 7B and 7C.

FIG. 7E is a diagram of a PUA communicating with the research datamonitor of FIGS. 7A, 7B and 7C.

The disclosed methods and systems, as well as particular features andadvantages of various embodiments thereof will become more apparent fromthe following detailed description considered with reference to theaccompanying drawings in which the same elements depicted in differentdrawing figures are assigned the same reference numerals.

FIG. 1 is a diagram illustrating certain embodiments of a research datagathering system 10. A monitoring device 12 is provided for receivingmonitored data. The monitoring device 12 can comprise either a singledevice or multiple devices, stationary at a source to be monitored, ormultiple devices, stationary at multiple sources to be monitored.Alternatively, the monitoring device 12 can be incorporated in aportable monitoring device that can be carried by an individual tomonitor various sources as the individual moves about.

Where acoustic data including media data, such as audio data, ismonitored, the monitoring device 12 typically would be an acoustictransducer such as a microphone, having an input which receives mediadata in the form of acoustic energy and which serves to transduce theacoustic energy to electrical data. Where media data in the form oflight energy, such as video data, is monitored, the monitoring device 12takes the form of a light-sensitive device, such as a photodiode, or avideo camera. Light energy including media data could be, for example,light emitted by a video display. The device 12 can also take the formof a magnetic pickup for sensing magnetic fields associated with aspeaker, a capacitive pickup for sensing electric fields or an antennafor electromagnetic energy. In still other embodiments, the device 12takes the form of an electrical connection to a monitored device, whichmay be a television, a radio, a cable converter, a satellite televisionsystem, a game playing system, a VCR, a DVD player, a portable player, acomputer, a web appliance, or the like. In still further embodiments,the monitoring device 12 is embodied in monitoring software running on acomputer to gather media data.

A processor 14, coupled to the monitoring device 12, is provided forprocessing the monitored data. Storage device 16, coupled to processor14, receives data from the processor 14 for storage. Communications 18is coupled with the processor 14 and is provided for communicating theprocessed data to a processing facility for use in preparing reportsincluding research data.

FIG. 2 is a diagram for use in explaining operation of certainembodiments of the system of FIG. 1. As shown at 20, time-domain audiodata is received by the monitoring device 12. Once received, thetime-domain audio data, representing the audio signal as it varies overtime, is converted by processor, as shown at 22, to frequency-domainaudio data, i.e., data representing the audio signal as it varies withfrequency. As will be understood by one of ordinary skill in the art,conversion from the time domain to the frequency domain may beaccomplished by any one of a number of existing techniques comprising,for instance, discrete Fourier transform, fast Fourier transform (FFT),DCT, wavelet transform, Hadamard transform or other time-to-frequencydomain transformation, or else by digital or analog filtering. Processor14 stores the frequency-domain audio data temporarily in storage 16.

Processor 14 processes the frequency-domain audio data to read anancillary code therefrom, as shown at 24, as well as to extract asignature therefrom, i.e., data expressing information inherent to anaudio signal, as shown at 26, for use in identifying the audio signal orobtaining other information concerning the audio signal (such as asource or distribution path thereof).

Where audio media includes ancillary codes, suitable decoding techniquesare employed to detect the encoded information, such as those disclosedin U.S. Pat. No. 5,450,490 and No. 5,764,763 to Jensen, et al., U.S.Pat. No. 5,579,124 to Aijala, et al., U.S. Pat. Nos. 5,574,962,5,581,800 and 5,787,334 to Fardeau, et al., U.S. Pat. No. 6,871,180 toNeuhauser, et al., U.S. Pat. No. 6,862,355 to Kolessar, et al., U.S.Pat. No. 6,845,360 to Jensen, et al., U.S. Pat. No. 5,319,735 to Preusset al., U.S. Pat. No. 5,687,191 to Lee, et al., U.S. Pat. No. 6,175,627to Petrovich et al., U.S. Pat. No. 5,828,325 to Wolosewicz et al., U.S.Pat. No. 6,154,484 to Lee et al., U.S. Pat. No. 5,945,932 to Smith etal., US 2001/0053190 to Srinivasan, US 2003/0110485 to Lu, et al., U.S.Pat. No. 5,737,025 to Dougherty, et al., US 2004/0170381 to Srinivasan,and WO 06/14362 to Srinivasan, et al., all of which hereby areincorporated by reference herein.

Examples of techniques for encoding ancillary codes in audio, and forreading such codes, are provided in Bender, et al., “Techniques for DataHiding”, IBM Systems Journal, Vol. 35, Nos. 3 & 4, 1996, which isincorporated herein by reference in its entirety. Bender, et al.disclose a technique for encoding audio termed “phase encoding” in whichsegments of the audio are transformed to the frequency domain, forexample, by a discrete Fourier transform (DFT), so that phase data isproduced for each segment. Then the phase data is modified to encode acode symbol, such as one bit. Processing of the phase encoded audio toread the code is carried out by synchronizing with the data sequence,and detecting the phase encoded data using the known values of thesegment length, the DFT points and the data interval.

Bender, et al. also describe spread spectrum encoding and decoding, ofwhich multiple embodiments are disclosed in the above-cited Aijala, etal. U.S. Pat. No. 5,579,124.

Still another audio encoding and decoding technique described by Bender,et al. is echo data hiding in which data is embedded in a host audiosignal by introducing an echo. Symbol states are represented by thevalues of the echo delays, and they are read by any appropriateprocessing that serves to evaluate the lengths and/or presence of theencoded delays.

A further technique, or category of techniques, termed “amplitudemodulation” is described in R. Walker, “Audio Watermarking”, BBCResearch and Development, 2004. In this category fall techniques thatmodify the envelope of the audio signal, for example by notching orotherwise modifying brief portions of the signal, or by subjecting theenvelope to longer term modifications. Processing the audio to read thecode can be achieved by detecting the transitions representing a notchor other modifications, or by accumulation or integration over a timeperiod comparable to the duration of an encoded symbol, or by anothersuitable technique.

Another category of techniques identified by Walker involvestransforming the audio from the time domain to some transform domain,such as a frequency domain, and then encoding by adding data orotherwise modifying the transformed audio. The domain transformation canbe carried out by a Fourier, DCT, Hadamard, Wavelet or othertransformation, or by digital or analog filtering. Encoding can beachieved by adding a modulated carrier or other data (such as noise,noise-like data or other symbols in the transform domain) or bymodifying the transformed audio, such as by notching or altering one ormore frequency bands, bins or combinations of bins, or by combiningthese methods. Still other related techniques modify the frequencydistribution of the audio data in the transform domain to encode.Psychoacoustic masking can be employed to render the codes inaudible orto reduce their prominence. Processing to read ancillary codes in audiodata encoded by techniques within this category typically involvestransforming the encoded audio to the transform domain and detecting theadditions or other modifications representing the codes.

A still further category of techniques identified by Walker involvesmodifying audio data encoded for compression (whether lossy or lossless)or other purpose, such as audio data encoded in an MP3 format or otherMPEG audio format, AC-3, DTS, ATRAC, WMA, RealAudio, Ogg Vorbis, APTX100, FLAC, Shorten, Monkey's Audio, or other. Encoding involvesmodifications to the encoded audio data, such as modifications to codingcoefficients and/or to predefined decision thresholds. Processing theaudio to read the code is carried out by detecting such modificationsusing knowledge of predefined audio encoding parameters.

It will be appreciated that various known encoding techniques may beemployed, either alone or in combination with the above-describedtechniques. Such known encoding techniques include, but are not limitedto FSK, PSK (such as BPSK), amplitude modulation, frequency modulationand phase modulation.

In certain embodiments, certain encoding techniques, such as thosedescribed in U.S. Pat. No. 6,871,180 to Neuhauser, et al., discloseaudio encoding techniques that encode audio with one or morecontinuously repeating messages, each including a number of code symbolsfollowing one after the other along a timebase of the audio signal. Eachcode symbol comprises a plurality of frequency components. In certainembodiments of system 10 that are adapted to read continuously repeatingmessages, acoustic energy, or, sound, picked up by the monitoring device12 is continuously monitored to detect the embedded symbols comprisingan encoded message. That is, decoding of an encoded message in the audiosignal occurs continuously throughout operation of the system 10. Indoing so, system 10 performs an FFT by means of processor 14 which iscarried out on a continuing basis transforming a time segment of theaudio signal to the frequency domain. In certain ones of suchembodiments, a segment thereof comprising a one-quarter second durationis transformed to the frequency domain using an FFT, such that thesegments overlap by, for example, 40%, 50%, 60%, 70% or 80%. System 10separately evaluates for each component of the frequency code symbols inthe encoded message whether the received energy comprises either amessage or noise first by formulating a quotient comprising anassociated energy value of a given frequency bin that would indicatesuch frequency components relative to a noise level associated withneighboring frequency bins. The noise level is obtained by averaging theenergy levels of a predetermined number of frequency ranges neighboringthe selected frequency bin being evaluated.

Storage 16 implements one or more accumulators for storage of thequotients associated with varying portions of the audio signal. Storage16, for instance comprising a first-in/first-out (FIFO) buffer, enableseach of the quotients to be continuously, repeatedly accumulated andsorted according to predetermined criteria. Such criteria comprises,optionally, a message length equal to that of the accumulator.Accordingly, where there are multiple messages simultaneously present inthe audio, each accumulator serves to accumulate the frequencycomponents of the code symbols in a respective one of the messages. Incertain ones of these embodiments, multiple messages are detected asdisclosed in U.S. Pat. No. 6,845,360 to Jensen, et al. Accumulation ofthe messages in this manner comprises an advantage of reducing theinfluence of noise which factors into the reading of the message.

As explained above, signatures are formed from the same audio data inthe frequency domain that is used to decode the encoded messages in theaudio.

Suitable techniques for extracting signatures include those disclosed inU.S. Pat. No. 5,612,729 to Ellis, et al. and in U.S. Pat. No. 4,739,398to Thomas, et al., each of which is assigned to the assignee of thepresent application and both of which are incorporated herein byreference in their entireties.

Still other suitable techniques are the subject of U.S. Pat. No.2,662,168 to Scherbatskoy, U.S. Pat. No. 3,919,479 to Moon, et al., U.S.Pat. No. 4,697,209 to Kiewit, et al., U.S. Pat. No. 4,677,466 to Lert,et al., U.S. Pat. No. 5,512,933 to Wheatley, et al., U.S. Pat. No.4,955,070 to Welsh, et al., U.S. Pat. No. 4,918,730 to Schulze, U.S.Pat. No. 4,843,562 to Kenyon, et al., U.S. Pat. No. 4,450,551 to Kenyon,et al., U.S. Pat. No. 4,230,990 to Lert, et al., U.S. Pat. No. 5,594,934to Lu, et al., European Published Patent Application EP 0887958 toBichsel, PCT Publication WO02/11123 to Wang, et al. and PCT publicationWO91/11062 to Young, et al., all of which are incorporated herein byreference in their entireties.

It is contemplated that system 10 comprise software and/or hardwareenabling the extraction of signatures from received audio signals. Thesoftware is configured to direct the processor 14 to retain the time atwhich a particular signature is extracted, and to direct storage thereofin storage 16. The signatures gathered by system 10 are communicated bycommunications 18 to a processing facility for matching with referencesignatures for identifying the broadcast audio signal, or portionthereof.

In certain embodiments, when using data resulting from an FFT performedacross a predetermined frequency range, the FFT data from an even numberof frequency bands (for example, eight, ten, sixteen or thirty twofrequency bands) spanning the predetermined frequency range are used twobands at a time during successive time intervals. FIG. 6 provides anexample of how pairs of the bands are selected in these embodimentsduring successive time intervals where the total number of bands used isequal to ten. The selected bands are indicated by an “X”.

When each band is selected, the energy values of the FFT bins withinsuch band and such time interval are processed to form one bit of thesignature. If there are ten FFT's for each time interval of the audiosignal, for example, the values of all bins of such band within thefirst five FFT's are summed to form a value “A” and the values of allbins of such band within the last five FFT's are summed to form a value“B”. In the case of a received broadcast audio signal, the value A isformed from portions of the audio signal that were broadcast prior tothose used to form the value B or which represent earlier portions ofthe audio signal relative to its time base.

To form a bit of the signature, the values A and B are compared. If B isgreater than A, the bit is assigned a value “1” and if A is greater thanor equal to B, the bit is assigned a value of “0”. Thus, during eachtime interval, two bits of the signature are produced.

Each bit of the signature is a representation of the energy content inthe band represented thereby during a predetermined time period, and maybe referred to as the “energy slope” thereof. Because any one energyslope is associated with a particular band, as opposed to beingassociated with a representation of energy content across a group ofbands or between certain ones of various bands, the impact offluctuations in the relative magnitudes of reproduced audio amongfrequency bands is virtually eliminated.

In certain embodiments, signatures are extracted continuously. In suchembodiments, information is obtained without a dependency on atriggering, predetermined event, or other type of prompting, and thusthrough uninterrupted information gathering, the signatures obtainedwill, necessarily, contain more information. For instance, thisadditional information is manifested in a signature, or portion thereof,that is formed of information as to how the audio signal changes overtime as well as with frequency. This is in contrast to signatureextraction occurring only upon prompting caused by a predetermined eventand detection thereof, whereby information then obtained is onlyrepresentative of the audio signal characterized within a certainisolated time frame.

Typically, frequency bins or bands of different size are employed toextract signatures and read codes. For example, relatively narrow binsizes, such as 2, 4 or 6 Hz are used to detect the presence of acomponent of an ancillary code, while signature extraction requires theuse of wider bands, such as 30, 40 or 60 Hz to ensure that the bandenergy is sufficient to permit the extraction of a reliable signature orsignature portion. Accordingly, in an advantageous embodiment of theinvention that employs a time domain-to-frequency domain transformationthat distributes the energy of an audio signal into a plurality offrequency bins or bands, the size or sizes of the bins or bands are eachselected to have a first, relatively narrow frequency width. The energyvalues of such frequency bins or bands are processed to read anancillary code therefrom. These energy values are also combined ingroups of contiguous bins or bands (such as by addition) to producefrequency band values each representing an energy level within afrequency band comprising the respective group. Such frequency bandvalues are then processed to extract a signature therefrom.

With reference to FIG. 3, which illustrates at least one of certainadvantageous embodiments of the system, a PUA 27 is shown which isconfigured for gathering research data. Audio data is received at themicrophone 28, which may also comprise a peripheral of the PUA 27allowing it to be located a distance from the remainder thereof shoulddoing so provide added convenience to the user. The audio data is thenconditioned and converted from its analog format to digital data, asshown at 30, in a manner understood by one of ordinary skill in the art.A programmable processor 32 coupled with the system then transforms thedigital data to the frequency domain, optionally by DFT, FFT or othertransform technique including DCT, wavelet transform, Hadamardtransform, or else by digital or analog filtering. The PUA 27 furthercomprises storage 34, comprising a buffer such as a FIFO bufferaddressed herein, for cooperation with the processor 32 in a manner wellunderstood by one of ordinary skill in the art, to both decode anancillary code and extract a signature from the single data set producedby, for example, an FFT. Communications 36 receives data processed bythe processor 32 and is coupled thereto for delivery to a remoteprocessing location. In certain embodiments, storage 34 serves to retaininformation not immediately transmitted to communications 36.

With reference to FIGS. 4 and 4A, there is illustrated a block diagramof a cellular telephone 38 modified to carry out a research operation.The cellular telephone 38 comprises a processor 40 operative to exerciseoverall control of the cellular telephone's operation and to processaudio and other data for transmission or reception. Communications 50 iscoupled to the processor 40 and is operative to establish and maintain atwo-way wireless communication link with a respective cell of a cellulartelephone network. In certain embodiments, processor 40 is configured toexecute applications apart from or in conjunction with the conduct ofcellular telephone communications, such as applications serving todownload audio and/or video data to be reproduced by the cellulartelephone, e-mail clients and applications enabling the user to playgames using the cellular telephone. In certain embodiments, processor 40comprises two or more processing devices, such as a first processingdevice (such as a digital signal processor) that processes audio, and asecond processing device that exercises overall control over operationof the cellular telephone. In certain embodiments, processor 40comprises a single processing device. In certain embodiments, some orall of the functions of processor are implemented by hardwiredcircuitry.

Cellular telephone 38 further comprises storage 60 coupled withprocessor 40 and operative to store data as needed. In certainembodiments, storage 60 comprises a single storage device, while inothers it comprises multiple storage devices. In certain embodiments, asingle device implements certain functions of both processor 40 andstorage 60.

In addition, cellular telephone 38 comprises a microphone 100 coupledwith processor 40 and serving to transduce the user's voice to anelectrical signal which it supplies to processor 40 for encoding, and aspeaker and/or earphone 70 coupled with processor 40 to transducereceived audio from processor 40 to an acoustic output to be heard bythe user. Cellular telephone 38 also includes a user input 80 coupledwith processor 40, such as a keypad, to enter telephone numbers andother control data, as well as a display 90 coupled with processor 40 toprovide data visually to the user under the control of processor 40.

In certain embodiments, cellular telephone 38 provides additionalfunctions and/or comprises additional elements. In certain ones of suchembodiments, the cellular telephone 38 provides e-mail, text messagingand/or web access through its wireless communications capabilities,providing access to media and other content. For example, Internetaccess via cellular telephone 38 enables access to video and/or audiocontent that can be reproduced by the cellular telephone 38 for theuser, such as songs, video on demand, video clips and streaming media.In certain embodiments, storage 60 stores software providing audioand/or video downloading and reproducing functionality, such as iPod®software, enabling the user to reproduce audio and/or video contentdownloaded from a source, such as a personal computer via communications50 or through direct Internet access via communications 50.

To enable cellular telephone 38 to gather research data, namely, dataindicating exposure to audio such as programs, music and advertisements,research software is installed therein to control processor 40 to gathersuch data and communicate it via communications 50 to a researchorganization. The research software in certain embodiments also controlsprocessor 40 to store the data in storage 60 for subsequentcommunication.

The research software controls the processor 40 to transduce thetime-domain audio data produced by microphone 100 to frequency domaindata and to read ancillary codes from the frequency domain data usingone or more of the known techniques identified hereinabove, and then tostore and/or communicate the codes that have been read for use asresearch data indicating encoded audio to which the user was exposed.The research software also controls the processor 40 to extractsignatures from the frequency domain data using one or more of the knowntechniques identified hereinabove, and then to store and/or communicatethe extracted signature data for use as research data which is thenmatched with reference signatures representing known audio to detect theaudio to which the user was exposed. In certain embodiments, theresearch software controls the processor 40 to store samples of thetransduced audio, either in compressed or uncompressed form forsubsequent processing to read ancillary codes therein and to extractsignatures therefrom after transformation to the frequency domain. Incertain embodiments, the research software is operative both to readcodes and extract signatures from the audio data, and selectively (a)both reads such codes and extracts such signatures from certain portionsof the audio data and/or (b) reads codes from certain portions of theaudio data and extracts signatures from other portions of the audiodata.

Where the cellular telephone 38 possesses functionality to downloadand/or reproduce presentation data, in certain embodiments, researchdata concerning the usage and/or exposure to such presentation data aswell as audio data received acoustically by microphone 100, is gatheredby cellular telephone 38 in accordance with the technique illustrated bythe functional block diagram of FIG. 4A. Storage 60 of FIG. 4 implementsan audio buffer 110 for audio data gathered with the use of microphone100. In certain ones of these embodiments storage 60 implements a buffer130 for presentation data downloaded and/or reproduced by cellulartelephone 38 to which the user is exposed via speaker and/or earphone 70or display 90, or by means of a device coupled with cellular telephone38 to receive the data therefrom to present it to a user. In some ofsuch embodiments, the reproduced data is obtained from downloaded data,such as songs, web pages or audio/video data (e.g., movies, televisionprograms, video clips). In some of such embodiments, the reproduced datais provided from a device such as a broadcast or satellite radioreceiver of the cellular telephone 38 (not shown for purposes ofsimplicity and clarity). In certain ones of these embodiments storage 60implements a buffer 130 for metadata of presentation data reproduced bycellular telephone 38 to which the user is exposed via speaker and/orearphone 70 or display 90, or by means of a device coupled with cellulartelephone 38 to receive the data therefrom to present it to a user. Suchmetadata can be, for example, a URL from which the presentation data wasobtained, channel tuning data, program identification data, anidentification of a prerecorded file from which the data was reproduced,or any data that identifies and/or characterizes the presentation data,or a source thereof. Where buffer 130 stores audio data, buffers 110 and130 store their audio data (either in the time domain or the frequencydomain) independently of one another. Where buffer 130 stores metadataof audio data, buffer 110 stores its audio data (either in the timedomain or the frequency domain) and buffer 130 stores its metadata, eachindependently of the other.

Processor 40 separately produces research data 120 from the contents ofeach of buffers 110 and 130 which it stores in storage 60. In certainones of these embodiments, one or both of buffers 110 and 130 is/areimplemented as circular buffers storing a predetermined amount oftime-domain audio data representing a most recent time interval thereofas received by microphone 100 and/or reproduced by speaker and/orearphone 70, or downloaded by cellular telephone 38 for reproduction bya different device coupled with cellular telephone 38. Processor 40extracts signatures and/or decodes ancillary codes in the buffered audiodata to produce research data 120 by converting the time-domain audiodata to frequency-domain audio data and processing the frequency-domainaudio data for reading an ancillary code therefrom and extracting asignature therefrom. Where metadata is received in buffer 130, incertain embodiments the metadata is used, in whole or in part, asresearch data, or processed to produce research data. The research datais thus gathered representing exposure to and/or usage of audio data bythe user where audio data is received in acoustic form by the cellulartelephone 38 and where presentation data is received in non-acousticform (for example, as a cellular telephone communication, as anelectrical signal via a cable from a personal computer or other device,as a broadcast or satellite signal or otherwise).

With reference again to FIG. 4, in certain embodiments, the cellulartelephone 38 comprises a research data source 42 coupled by a wired orwireless coupling with processor 40 for use in gathering further oralternative research data to be communicated to a research organization.In certain ones of these embodiments, the research data source 42comprises a location data producing device or function providing dataindicating a location of the cellular telephone 38. Various devicesappropriate for use as the research data source 42 include a satellitelocation signal receiver, a terrestrial location signal receiver, awireless networking device that receives location data from a network,an inertial location monitoring device and a location data producingservice provided by a cellular telephone service provider. In certainembodiments, research data source 42 comprises a device or function formonitoring exposure to print media, for determining whether the user isat home or out of home, for monitoring exposure to products, exposure todisplays (such as outdoor advertising), presence within or nearcommercial establishments, or for gathering research data (such asconsumer attitude, preference or opinion data) through theadministration of a survey to the user of the cellular telephone 38. Incertain embodiments, research data source 42 comprises one or moredevices for receiving, sensing or detecting data useful in implementingone or more of the foregoing functions, other research data gatheringfunctions and/or for producing data ancillary to functions of gathering,storing and/or communicating research data, such as data indicatingwhether the panelist has complied with predetermined rules governing theactivity or an extent of such compliance. Such devices include, but arenot limited to, motion detectors, accelerometers, temperature detectors,proximity detectors, satellite positioning signal receivers, RFIDreaders, RF receivers, wireless networking transceivers, wireless devicecoupling transceivers, pressure detectors, deformation detectors,electric field sensors, magnetic field sensors, optical sensors,electrodes, and the like.

With reference to FIG. 5, there is illustrated a personal digitalassistant (PDA) 200 modified to gather research data. The PDA 200comprises a processor 210 operative to exercise overall control and toprocess data for, among other purposes, transmission or reception by thePDA 200. Communications 220 is coupled to the processor 210 and isoperative under the control of processor 210 to perform those functionsrequired for establishing and maintaining two-way communications over anetwork (not shown for purposes of simplicity and clarity).

In certain embodiments, processor 210 comprises two or more processingdevices, such as a first processing device that controls overalloperation of the PDA 200 and a second processing device that performscertain more specific operations such as digital signal processing. Incertain embodiments, processor 210 employs a single processing device.In certain embodiments, some or all of the functions of processor 210are implemented by hardwired circuitry.

PDA 200 further comprises storage 230 coupled with processor 210 andoperative to store software that runs on processor 210, as well astemporary data as needed. In certain embodiments, storage 230 comprisesa single storage device, while in others it comprises multiple storagedevices. In certain embodiments, a single device implements certainfunctions of both processor 210 and storage 230.

PDA 200 also includes a user input 240 coupled with processor 210, suchas a keypad, to enter commands and data, as well as a display 250coupled with processor 210 to provide data visually to the user underthe control of processor 210.

In certain embodiments, the PDA 200 provides additional functions and/orcomprises additional elements. In certain embodiments, PDA 200 providescellular telephone functionality, and comprises a microphone and audiooutput (not shown for purposes of simplicity and clarity), as well as anability of communications 220 to communicate wirelessly with a cell of acellular telephone network, to enable its operation as a cellulartelephone. Where PDA 200 possesses cellular telephone functionality, incertain embodiments PDA 200 is employed to gather, store and/orcommunicate research data in the same manner as cellular telephone 38(such as by storing appropriate research software in storage to run onprocessor), and communicates with system 10 in the same manner to setup, promote, operate, maintain and/or terminate a research operationusing PDA 200.

In certain embodiments, communications 220 of PDA 200 provides wirelesscommunications via Bluetooth protocol, ZigBee™ protocol, wireless LANprotocol, infrared data link, inductive link or the like, to a network,network host or other device, and/or through a cable to such a network,network host or other device. In such embodiments, PDA 200 is employedto gather, store and/or communicate research data in the same manner ascellular telephone 38 (such as by storing appropriate research softwarein storage to run on processor), and communicates with system 10 in thesame manner (either through a wireless link or through a connection,such as a cable) to set up, promote, operate, maintain and/or terminatea research operation using PDA 200.

PDA 200 receives audio data in the form of acoustic data and/or audiodata communicated in electronic form via a wireless or wired link. PDAstores research software enabling PDA 200 to gather research data,namely, data indicating exposure to such audio data, by controllingprocessor 210 to gather such data and communicate it via communications220 to a research organization. The research software in certainembodiments also controls processor 210 to store the data in storage 230for subsequent communication. That is, processor 210 is controlled toread codes from the audio data and extract signatures therefrom in thesame manner as any one or more of the embodiments explained hereinabove.

In certain embodiments, the PDA 200 comprises a research data source 260coupled by a wired or wireless coupling with processor 210 for use ingathering further or alternative research data to be communicated to aresearch organization. In certain ones of these embodiments, theresearch data source 260 comprises a location data producing device orfunction providing data indicating a location of the cellular telephonePDA 200. Various devices appropriate for use as source include asatellite location signal receiver, a terrestrial location signalreceiver, a wireless networking device that receives location data froma network, an inertial location monitoring device and a location dataproducing service provided by a cellular telephone service provider. Incertain ones of these embodiments, research data source 260 comprises adevice or function for monitoring exposure to print media, fordetermining whether the user is at home or out of home, for monitoringexposure to products, exposure to displays (such as outdooradvertising), presence within or near commercial establishments, or forgathering research data (such as consumer attitude, preference oropinion data) through the administration of a survey to the user of thePDA 200. In certain ones of these embodiments, research data sourcecomprises one or more devices for receiving, sensing or detecting datauseful in implementing one or more of the foregoing functions, otherresearch data gathering functions and/or for producing data ancillary tofunctions of gathering, storing and/or communicating research data, suchas data indicating whether the panelist has complied with predeterminedrules governing the activity or an extent of such compliance. Suchdevices include, but are not limited to, motion detectors,accelerometers, temperature detectors, proximity detectors, satellitepositioning signal receivers, RFID readers, RF receivers, wirelessnetworking transceivers, wireless device coupling transceivers, pressuredetectors, deformation detectors, electric field sensors, magnetic fieldsensors, optical sensors, electrodes, and the like.

FIG. 7 illustrates a PUA 21 coupled by its communications 41 withcommunications 211 of a research system 201 comprising a microphone 221,a processor 231 coupled with microphone 221 and with communications 211by a wired or wireless link. Research system 201 in certain embodimentscomprises storage 241 coupled with processor 231. In certainembodiments, communications 41 is operative to communicate data to aresearch data processing facility. In certain embodiments,communications 41 is further operative to communicate data with theresearch system 201. Such communications between the PUA 21 and researchsystem 201 may be triggered by, for example, either (1) the elapse of apredetermined interval of time, (2) production of a communicationsrequest or query by either the PUA 21 or the research system 201, (3)the storage of a predetermined amount of data by either PUA 21 and/orresearch system 201, (4) proximity of PUA 21 and the research system201, or (5) any combination of (1)-(4). In certain embodiments,communications 41 of PUA 21 comprises a transceiver configured tocommunicate using a Bluetooth protocol, ZigBee™ protocol, wireless LANprotocol, or via an infrared data link, inductive link or the like, forenabling communications with the research system 201 as well as with anetwork, network host or other device to communicate data to a researchdata processing facility. In certain embodiments, communications 41 ofPUA 21 comprises a first transceiver configured to communicate withresearch system 201 and a second transceiver (such as a cellulartelephone transceiver) configured to communicate with the research dataprocessing facility.

In certain embodiments research system 201 is housed separately from PUA21 and is physically separated therefrom, but both are carried on theperson of a panelist. In certain embodiments, research system 201 ishoused separately from PUA 21 but is either (1) affixed to an exteriorsurface thereof, (2) carried by or in a common container or carriagedevice with PUA 21, (3) carried by or in a cover of PUA 21 (such as adecorative “skin”), or (4) arranged to contain PUA 21. In certainembodiments, PUA 21 and research system 201 are contained by a commonhousing.

In certain ones of such embodiments, processor 231 of research system201 serves to read ancillary codes and extract signatures from audiodata transduced by the microphone 221 in the manner described above inconnection with the embodiments of FIGS. 1 through 5. Certain ones ofthese embodiments communicate the ancillary codes that have been readand the signatures that have been extracted to the PUA 21 bycommunications 211 for storage and/or communication from the PUA.

In certain ones of these embodiments, storage 241 serves to store theancillary codes and/or signatures for subsequent communication to thePUA 21.

In certain ones of such embodiments, research system 201 serves to storeaudio data transduced by the microphone 221 in storage 241, andsubsequently communicates the audio data to PUA 21 via communications211. PUA 21 processes the audio data as described hereinabove to produceresearch data therefrom.

In certain ones of such embodiments, research system 201 receives audiodata from PUA 21 via communications 211 and processor 231 serves toproduce research data from the audio data which either is stored instorage 241 and subsequently communicated to PUA 21 by communications211 or communicated thereby without prior storage in research system201.

In certain ones of such embodiments, processor 231 of research system201 receives presentation data and/or metadata of the presentation datafrom PUA 21 via communications 211 and processes the presentation dataand/or metadata to produce research data therefrom. Such presentationdata and metadata is received by PUA 21 in a form other than acousticdata such as electrical or electromagnetic data. Research system 201either stores such research data in storage 241 and subsequentlycommunicates it to PUA 21 by communications 211, or communicates theresearch data to PUA 21 by communications 211 without prior storage inresearch system 201.

In certain embodiments of research system 201, processor 231 adds a timeand/or date stamp to research data, media data, presentation data ormetadata of one of the foregoing received, produced, stored orcommunicated thereby.

In certain ones of such embodiments, research system 201 receives audiodata, presentation data and/or metadata of one of the foregoing from PUA21 via communications 211 and stores the received data in storage 241.Subsequently, system 201 reads the stored data from storage 241 andcommunicates it to PUA 21 which either processes it to produce researchdata therefrom or communicates it to a processing facility for producingresearch data. Communication of the research data from the PUA 21affords a number of advantages. At least a first advantage includesbeing able to provide a user a research system of smaller size and lowerweight since (1) it need not itself comprise hardware enablingcommunication of the research data to the processing facility, (2) asmaller power source, commonly a battery, thus decreasing the size andweight of the research system may be used for operation thereof, and (3)less data storage capacity is necessary in the research system given theopportunity for frequent communication of research data between the PUA21 and the research system 201. At least a second advantage includes anopportunity for increased frequency of reporting of the research data tothe research data processing facility since the PUA 21 is readilyavailable for the communication thereof.

In certain ones of the foregoing embodiments, PUA 21 gathers media dataresearch data from media data received thereby in non-acoustic formand/or metadata of such media data. PUA 21 either stores such media dataresearch data and later communicates it to a research organization viacommunications 41, or communicates it without first storing it. Incertain ones of such embodiments, PUA 21 receives audio data researchdata from system 201 produced thereby from audio data, and communicatesthe audio data research data to a research organization viacommunications 41. In certain ones of such embodiments, PUA 21 combinesthe audio data research data and the media data research data forcommunication to a research organization via communications 41.

FIG. 7A illustrates a research data monitor 72 affixed to an outersurface 23 of a PUA 21A, wherein the monitor 72 is operative in certainembodiments to gather research data and communicate it to PUA 21A whichin turn communicates the research data to a processing facility for usein preparing reports including research data. PUA 21A is illustrated inthe block diagram of FIG. 7B. In certain embodiments, monitor 72implements one or more of the research operations described above inconnection with FIG. 7. As shown in FIG. 7B, PUA 21A comprises the sameelements as PUA 38 of FIG. 4, except that research data source 96 isomitted from the embodiment of FIG. 7B.

Research data monitor 72 is illustrated in the block diagram of FIG. 7C.The research data monitor 72 comprises a processor 74 that is operativeto exercise overall control of the monitor 72 and to process data fortransmission or reception and communications 82 coupled to the processor74 and operative under the control of processor 74 to perform thosefunctions required for conducting communications with PUA 21A. Incertain embodiments, processor 74 comprises two or more processingdevices, such as a first processing device (such as a digital signalprocessor) that processes research data, such as audio data, and asecond processing device that exercises overall control over operationof the monitor 72. In certain embodiments, processor 74 employs a singleprocessing device. In certain embodiments, some or all of the functionsof processor 74 are implemented by software, while in other embodiments,the functions of processor 74 are implemented in hardwired circuitrywithout the use of software.

In certain embodiments, communications 82 establishes and maintains awireless communication link with communications 50 of PUA 21A, using aBluetooth™ protocol, a ZigBee™ protocol, an inductive link, a capacitivelink, an RF link, infrared link, or otherwise. In certain embodiments,communications 82 communicates with communications 50 using a wiredlink, such as a USB interface, a Firewire® interface, a connection to aplug or jack of the PUA 21A or an internal connection to PUA 21A.

Research data monitor 72 further comprises a research data source 76coupled with processor 74. In certain embodiments, research data monitor72 comprises a microphone that serves to transduce acoustic energy forprocessing by processor 74 to produce research data. In certainembodiments, research data source 76 comprises a keypad that enables theuser to input data, such as channel or station data, user identificationdata or another kind of research data. In certain embodiments, monitor72 comprises an RF receiver and/or infrared radiation detector. Incertain embodiments, monitor 72 comprises a location data producingdevice or function providing data indicating a location of the monitor72. Various devices appropriate for use as research data source 76include a satellite location signal receiver, a terrestrial locationsignal receiver, a wireless networking device that receives locationdata from a network, an inertial location monitoring device and alocation data producing service provided by a PUA service provider. Incertain embodiments, monitor 76 comprises a device or function formonitoring exposure to print media, for determining whether the user isat home or out of home, for monitoring exposure to products, exposure todisplays (such as outdoor advertising), presence within or nearcommercial establishments, or for gathering research data (such asconsumer attitude, preference or opinion data) through theadministration of a survey to the user of the PUA 21A. In certainembodiments, monitor 76 comprises one or more devices for receiving,sensing or detecting data useful in implementing one or more of theforegoing functions, other research data gathering functions and/or forproducing data ancillary to functions of gathering, storing and/orcommunicating research data, such as data indicating whether thepanelist has complied with predetermined rules governing the activity oran extent of such compliance. Such devices include, but are not limitedto, motion detectors, accelerometers, temperature detectors, proximitydetectors, satellite positioning signal receivers, RFID readers, RFreceivers, wireless networking transceivers, wireless device couplingtransceivers, pressure detectors, deformation detectors, electric fieldsensors, magnetic field sensors, optical sensors, electrodes, and thelike.

Monitor 72 further comprises storage 78 coupled with processor 74 andoperative to store data as needed. In certain embodiments, storage 78comprises a single storage device, while in others it comprises multiplestorage devices. In certain embodiments, a single device implementscertain functions of both processor 74 and storage 78.

FIG. 7D illustrates an embodiment of research data monitor 72 fabricatedon a substrate 83, such as a printed circuit board or a flexiblesubstrate comprising paper, plastic or the like, on which certainelements of monitor 72 are printed on substrate 83. Power source 86comprises a battery (either rechargeable or non-rechargeable) or acharge storage device such as a capacitor, printed on substrate 83. Inthe embodiment of FIG. 7D, communications 82 comprises an RFtransceiver, such as a Bluetooth™ transceiver, a ZigBee™ transceiver orother RF transceiver. An antenna 92 is printed on substrate 83 andcoupled with communications 82. It will be appreciated that monitor 72can be fabricated to have a very thin profile and very low weight, sothat it may be affixed to the enclosure of a cellular telephone, a PDAor other PUA that is carried on the person of a participant, withoutadding substantially to its size or weight. In certain embodiments, themonitor 72 is carried by a cover for the PUA (such as a decorative“skin”). In certain embodiments, monitor 72 is housed in or carried by adevice separate from the PUA and adapted to be carried with the personof a panelist who carries the PUA.

FIG. 7E is a block diagram of a PUA comprising a personal communicationdevice adapted to be carried on the person of a participant (such as aPDA, Blackberry® device, pager, notebook computer, walkie talkie, or thelike) having a processor 94, and communications 95, user data source 96and storage 97 coupled with processor 94. A research data gatheringdevice 93, adapted to be carried on the person of a participant, isoperative to gather research data and communicate the same wirelessly tocommunications 95 of the personal communication device for subsequentcommunication by the personal communication device to a research dataprocessing facility. In certain embodiments, the research data gatheringdevice 93 is separate from the personal communication device, so that itis carried by the participant separately therefrom. In certain ones ofsuch embodiments, the device 93 is contained in a PUA such as an articleof jewelry, an article of clothing, a fob, a wristwatch or other PUA. Incertain ones of such embodiments, the device 93 is contained in its ownenclosure and is carried on a lanyard to be worn about the participant'sneck or provided with a pin, clasp or belt clip for attachment to anarticle of the participant's clothing.

As noted hereinabove, research software is provided to those of theforegoing devices implementing research operations by means ofprogrammed processors. In certain embodiments, the research software isstored at the time of manufacture. In others, it is installedsubsequently, either by a distributor, retailer, user, service provider,research organization or other entity by download to the respectivedevice or by installation of a storage device storing the researchsoftware as firmware, or otherwise.

Although various embodiments have been described with reference to aparticular arrangement of parts, features and the like, these are notintended to exhaust all possible arrangements or features, and indeedmany other embodiments, modifications and variations will beascertainable to those of skill in the art.

1. A method of gathering research data in a portable audience monitoringdevice, comprising: receiving time domain audio media data in a portableaudience monitoring device of an audience member; converting the timedomain audio media data to frequency domain data; and processing thefrequency domain data for reading an ancillary code therefrom and forextracting a signature therefrom.
 2. The method of claim 1, whereinconversion of the time domain audio data to the frequency domain audiodata is performed by a time domain-to-frequency domain transformation.3. The method of claim 2, wherein the frequency domain data is processedcontinuously throughout an audio media data monitoring operation of theportable monitoring device.
 4. The method of claim 3, comprisingconverting time-displaced segments of the audio media data to thefrequency domain, wherein the segments substantially overlap in time. 5.The method of claim 4, wherein the ancillary code comprises a messagecomprising code symbols each including a plurality of frequencycomponents; and comprising evaluating a signal level for each componentof the code symbols in the frequency domain data.
 6. The method of claim5, wherein noise is associated with a quotient comprising an associatedreceived energy value of a predetermined frequency bin indicatingfrequency components relative to a noise level associated with frequencybins in proximity to the predetermined frequency bin.
 7. The method ofclaim 6, further comprising: calculating the noise level by averagingenergy levels associated with a predetermined number of frequency rangesin proximity to the predetermined frequency bin.
 8. The method of claim6, further comprising storing data representing evaluations of thefrequency components.
 9. The method of claim 8, wherein the storage isimplemented by at least one accumulator.
 10. The method of claim 9,wherein the storage comprises at least one buffer enabling each of thevarious quotients to be continuously, repeatedly accumulated and sortedaccording to predetermined criteria.
 11. The method of claim 10, whereinthe predetermined criteria comprise, at least, a message length equal tothat of the accumulator.
 12. The method of claim 11, further comprising:where the time domain audio media data comprises multiple messages,accumulating the frequency components of the code symbols in respectiveones of the multiple messages.
 13. The method of claim 1, furthercomprising: providing software enabling the extraction of signatures.14. The method of claim 13, wherein the software is adapted to directthe processor to store the time at which a signature is extracted. 15.The method of claim 14, wherein the software is adapted to directstorage of the time associated with a particular signature extraction.16. The method of claim 3, wherein the time domain-to-frequency domaintransformation is carried out across a predetermined frequency range.17. The method of claim 16, further comprising: selecting frequencydomain audio data from across an even number of frequency bands withinthe predetermined frequency range according to a pairing of the bandsacross successive time intervals to produce a signature.
 18. The methodof claim 16, further comprising: forming signature data throughcomparison of the energy content of time displaced segments within eachof a plurality of the frequency bands.
 17. The method of claim 18,wherein the signature data comprises a compilation of bits each based ona respective comparison.
 18. The method of claim 1, further comprising:configuring a cellular telephone to provide the portable audiencemonitoring device.
 19. The method of claim 1, further comprising:configuring a PDA to provide the portable audience monitoring device.20. The method of claim 1, comprising converting the time domain audiomedia data to frequency domain data comprising energy values of each ofa plurality of frequency bins or bands each selected to have a first,relatively narrow frequency width, processing the energy values to readan ancillary code, combining the energy values in selected groups ofcontiguous bins or bands to produce frequency band values for respectiveones of a plurality of frequency bands each having a second widthgreater than the first, relatively narrow widths of the frequency binsor bands of the respective group, and processing the frequency bandvalues to extract a signature therefrom.
 21. A portable research datagathering device, comprising: an input arranged to receive time domainaudio media data; and a processor coupled with the input to receive thetime domain audio media data therefrom and configured to convert thetime domain audio media data to frequency domain data, and to processthe frequency domain data to read an ancillary code therefrom andextract a signature therefrom.
 22. The portable research data gatheringdevice of claim 21, wherein the processor is operative to process afirst portion of the frequency domain data to read the ancillary codetherefrom and to process a second portion of the frequency domain datato extract the signature therefrom, the second portion of the frequencydomain data differing at least in part from the first portion of thefrequency domain data.
 23. The portable research data gathering deviceof claim 22, wherein the first portion of the frequency domain datacorresponds to a first time segment of the time domain audio media dataand the second portion of the frequency domain data corresponds to asecond time segment of the time domain audio media data differing atleast in part from the first time segment thereof.
 24. A method ofgathering research data, comprising: receiving media data in a portableaudience monitoring device; converting the media data to a frequencydomain to produce frequency domain data; and extracting a signature fromthe frequency domain data and reading an ancillary code therefrom.
 25. Amethod of gathering research data concerning usage of and/or exposure tomedia data, comprising: receiving frequency domain data comprising datarepresenting magnitudes of the media data in different respectivefrequency bands; and reading an ancillary code from the frequency domaindata and extracting a signature from the frequency domain data.